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Nitrogen regulation by natural systems in“unnatural”landscapes:denitrif.cation in ultra-urban coastal ecosystems

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Ecosystem Health and Sustainability 2018年第9期4卷 17-37页

作者： Bernice R.Rosenzweig peter M.Grof.man Chester B.Zarnoch Brett f.Branco Ellen k.Hartig James f.tzpatrick.Helen M.f.rgione Adam Parris Environmental Sciences Initiative Advanced Science Research Center at the Graduate CenterCity University of New YorkNew YorkNYUSA Earth and Environmental Sciences Brooklyn CollegeCity University of New YorkBrooklynNYUSA Cary Institute of.Ecosystem Studies MillbrookNYUSA Natural Sciences Baruch College and Graduate CenterCity University of New YorkNew YorkNYUSA New York.City Department of.Park. and Recreation Natural Resources GroupNew YorkNYUSA HDR Inc.New YorkNYUSA The Natural Areas Conservancy New YorkNYUSA Science and Resilience Institute at Jamaica Bay BrooklynNYUSA

Dense cities represent biogeochemical hot spots along the shoreline,concentrating f.xed nitrogen that is subsequently discharged into adjacent coastal receiving ***,the ecosystem services provided by natural systems in highly urban environments can play a particularly important role in the global nitrogen *** this paper,we review the recent literature on nitrogen regulation by temperate coastal ecosystems,with a f.cus on how the distinct physical and biogeochemical f.atures of.the urban landscape can af.ect the provision of.this ecosystem *** use Jamaica Bay,an ultra-urbanized coastal lagoon in the United States of.America,as a demonstrative case *** on simple areal and tidal-based calculations,the natural systems of.Jamaica Bay remove~24%of.the reactive nitrogen discharged by wastewater treatment ***,this estimate does not represent the dynamic nature of.urban nitrogen cycling represented in the recent literature and highlights k.y research needs and *** review reveals that ecosystem-f.cilitated denitrif.cation may be signif.cant in even the most densely urbanized coastal landscapes,but critical uncertainties currently limit incorporation of.this ecosystem service in environmental management.

关键词： Nitrogen denitrif.cation urban coastal anammox wetlands

Canopy gap size inf.uences niche partitioning of.the ground-layer plant community in a northern temperate f.rest

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Journal of.Plant Ecology 2013年第1期6卷 92-100页

作者： Christel C.k.rn Rebecca A.Montgomery peter B.Reich Terry f.Strong USDA f.rest Service Northern Research Station1831 Hwy 169 EastGrand RapidsMN 55744USA Department of.f.rest Resources University of Minnesota-Twin Cities1530 North Cleveland AvenueSaint PaulMN 55108USA Hawk.sbury Institute f.r the Environment University of Western SydneyLocked Bag 1797Penrith NSW 2751Australia USDA f.rest Service USARetired

Aims The Gap Partitioning Hypothesis(GPH)posits that gaps create heterogeneity in resources crucial f.r tree regeneration in closed-canopy f.rests,allowing trees with contrasting strategies to coexist along resource *** studies have examined gap partitioning of.temperate,ground-layer vascular *** used a ground-layer plant community of.a temperate deciduous f.rest in northern Wisconsin,USA,as a model system to test whether the GPH extends to the relatively species-rich ground *** We used a well-replicated experimental approach that included a gap opening gradient(f.ve gap sizes,6,10,20,30 and 46 m diameter,and undisturbed ref.rence areas),a within-gap location gradient(gap edge to center),and a temporal gradient(0,2,6 and 13 years af.er gap creation).The data were observations of.ground-layer plant abundance,published plant traits,and a modeled index of.understory light *** ordinated the plant abundance data and evaluated the relationships of.composition,traits and light environment by gap size,location along the f.rest-gap transect and time,with several approaches such as correlations,descriptive statistics,non-parametric tests of.group dif.erences and indicator species importance *** f.ndings Ground-layer plant composition and traits dif.ered across gap sizes,within-gap locations and over *** of.all sizes dif.ered in composition f.om undisturbed areas,and all pair-wise combinations of.gap size also dif.ered in composition,except the 6 m f.om the 10-m *** gaps(46 m)also displayed within-gap compositional gradients f.om gap edge to center *** dif.erences in gap size were evident 2 years af.er gap creation and,contrary to our hypotheses,remained dif.erent over the 13-year period,even in gaps with crown *** contrast to the neutral theory,species f.nctional traits and microenvironmental conditions were related to variation in ground-layer *** with smaller seeds,low

关键词： herbaceous layer experimental gaps proximity to edge f.nctional diversity plant traits

Training and learning curves in minimally invasive pancreatic surgery:f.om simulation to mastery

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Journal of.Pancreatology 2020年第2期3卷 101-110页

作者： Haney Caelán M. k.radza Emir Limen Eldridge f. de Santibanes Martin k.nny-k.ster Benedict Müller Philip C. Bintintan Vasile V. k.lu Yak.b Hack.rt Thilo Müller-Stich Beat-peter Nick.l f.lix Department of.General Visceral and Transplantation SurgeryHeidelberg University HospitalHeidelbergGermany Department of.Surgery Hospital Italiano de Buenos AiresBuenos AiresArgentina Department of.Surgery Clinic Beau-SiteBernSwitzerland Department of.Surgery University Hospital Cluj NapocaCluj NapocaRomania

Back.round:Minimally invasive pancreatic surgery(MIPS)has developed over the last 3 decades and is nowadays experiencing an increased interest f.om the surgical *** increasing awareness of.both the public and the surgical community on patient saf.ty,optimization of.training has gained *** implementation of.MIPS we propose 3 training *** f.rst phase f.cuses on developing basic sk.lls and procedure specif.c sk.lls with the help of.simulation,biotissue drills,video libraries,live case observations,and training *** second phase consists of.index procedures,f.llowships,and proctoring programs to ensure patient saf.ty during the f.rst *** the third phase the surgeons aim is to saf.ly implement the procedure into standard practice while minimizing learning curve related excess morbidity and *** selection,sk.lls assessment,f.edback.and mentoring are important methods to optimize this *** residual learning curve can reach up to 100 cases depending on the surgeons’previous experience,selection of.cases,and def.nition of.the parameters used to assess the learning *** training and high procedural volume are k.y to implementing MIPS saf.ly.

关键词： Laparoscopic surgery Minimally invasive surgery Robotic surgery Training

10-Years Land Use Changes Decrease Landscape Integrity in a Brazilian Hydrographic Basin

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Journal of.Geographic Inf.rmation System 2017年第2期9卷 221-243页

作者： Luciana S. Estevam Julia Arieira peter Zeilhof.r Débora f. Calheiros Enviromental Sciences Universidade de Cuiabá (UNIC) Cuiabá Brazil Departamento de Ciências Ambientais Universidade de Cuiabá (UNIC)Cuiabá Brazil Instituto de Geograf.a História e Documenta&ccedil ã o Departamento de Geografia Universidade Federal de Mato Grosso (UFMT) Cuiabá Brazil Instituto de Geograf.a História e Documenta&ccedil ã o Departamento de Geografia Universidade Federal de Mato Grosso (UFMT) Cuiabá Brazil. Embrapa Pantanal Corumbá Brazil

Changes in land use associated with the suppression of.native vegetation can greatly alter the landscape conf.guration, af.ecting biodiversity and environmental services availability. This study analyzes how changes in land use af.ect landscape patterns of.vegetation remnant over a 10 year period. We quantif.ed spatial landscape patterns throughout a hydrographic basin f.r the years 2002, 2008, 2010 and 2012, using nine landscape metrics. An indicator of.integrity was used to details the transf.rmation processes occurring in the basin that could be used to monitor the impact of.landscape changes and its spatial patterning. Results showed that over this decade, extension of.f.rming activities reduced the cover of.native vegetation by 4.4%, with grassy-woody savanna, wooded savanna and f.rested savanna impacted especially strongly. Suppression of.vegetation across this period reduced the size of.f.agments and their connectivity. The landscape f.agmentation indicator indicated that the f.agmentation pattern varied spatially, with the upland areas along river headwaters, being most f.agmented. Areas of.f.oodplains vegetation, belonged to the Pantanal Wetland, although in better integrity states, are the most threatened by current pressures of.land use change. An intense recovery program f.r headwaters and aquif.r recharge areas, as well as riparian f.rests, is recommended to avoid the f.ture depletion of.water production. Besides, we also recommend the maintenance and recovering of.the connectivity of.the current remaining patches of.natural vegetation corridors and elaboration of.specif.c laws that incoporate the consolidated scientif.c k.owladge about wetland ecosystem f.nctioning, lik. the Pantanal.

关键词： Connectivity GIS Metrics Catchment Area f.agmentation Remnant Vegetation

Hospital-Adapted Clonal Complex 17 <i>Enterococcus f.ecium</i>f.und among Sand Enterococcal Isolates

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Journal of.Environmental Protection 2012年第1期3卷 74-82页

作者： Daniela Pinto Marta Ruivo peter Vandamme Maria de f. S. Lopes 不详

Though poorly studied, sand is an environment with an extended degree of.interaction with man. Enterococcal strains can be f.und in sand but we do not k.ow to what extent these ubiquitous opportunistic nosocomial pathogens isolated f.om sand carry antimicrobial resistances and virulence traits. In an attempt to f.ll in this k.owledge gap, two distinct types of.sand (beach and children playground) were examined concerning composition in enterococcal species, genetic diversity of.isolates and abundance of.resistance to antimicrobials and virulence traits. f.ve dif.erent species were f.und, namely Enterococcus f.ecium, Enterococcus f.ecalis, Enterococcus hirae, Enterococcus f.avescens and Enterococcus casselif.avus. Although genetic diversity was evident, two dif.erent E. f.ecium clones, common to the two types of.sand, were detected, suggesting the existence of.clones well adapted to this specif.c environment or f.om a common source. E. f.ecium was associated with multiple antibiotic resistances, including to f.uoroquinolones and tetracycline that are commonly used by veterinarians and clinicians. Among the multiresistant E. f.ecium strains f.om beach sand, two were f.om sequence type (ST) 442, which belongs to the wide-spread Hospital-adapted clade CC17. They both carried the esp gene and the genomic island associated with CC17. The other virulence f.ctors screened were disseminated among E. f.ecalis strains, but seldom detected in the other species, evidencing the existence, in these environments, of.E. f.ecalis strains carrying the same virulence f.ctors as the clinical ones. The present work.thus stresses the need to f.llow-up the presence and characterization of.enterococcal strains f.om both beach and children playground sands and of.including these environments in the epidemiological global analysis of.enterococcal isolates.

关键词： Antibiotic Resistance Beach Sand Clonal Complex 17 Enterococcus Playground Sand Virulence f.ctors

Applicability of.Dimedone Assays f.r the Development of.Online Aldehyde Sensor in Seawater f.ooding Systems

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Journal of.Sensor Technology 2016年第4期6卷 101-109页

作者： Mohammed A. Al-Moniee Cees k.opal Naim Ak.al Sjaak.van Veen Xiangyang Zhu peter f. Sanders peter f. Sanders f.had N. Al-Abeedi Ayman M. Amer Saudi Arabian Oil Company (Saudi Aramco) Dhahran KSA TNO (Netherlands Organization f.r Applied Scientif.c Research) Zeist The Netherlands

Biocides are oilf.eld chemicals that are widely used to control bacterial activity throughout the oil industry. A f.asibility study has been explored to develop detection techniques f.r biocide batch treatments, pref.rably on-line and in real-time, f.r their potential use in seawater f.ooding system. Several methods to measure k.y components of.the biocide f.rmulation were investigated and reported in previous study [1]. The enzymatic activity of.an immobilized acetylcholine esterase (AChE) on the column material was successf.lly inhibited by some model compounds, but not by the actual biocides commonly used in Saudi Aramco seawater f.ooding system. In this paper, an alternative assay f.r biocide detection in the Saudi Aramco seawater f.ooding system was investigated f.r its applicability f.r the development of.on-line biocide sensor. The assay was based on the detection of.aldehyde f.nctionality in the biocide mixture through measurement of.a f.uorescent derivative f.rmed in the reaction of.aldehyde groups and dimedone in the presence of.ammonium acetate. The reaction of.aldehyde groups with dimedone was demonstrated in seawater matrix, and the f.rmed f.uorescent product was successf.lly measured. The results showed that the dimedone-based assay was very sensitive, and relatively straightf.rward to perf.rm. The ruggedness test also indicated that the assay is sensitive to minor changes of.various specif.c conditions of.the method. It is concluded that the dimedone assay is suitable f.r f.rther development of.a real-time biocide monitoring system to detect the presence of.biocide slugs in seawater f.ooding system. The development of.an automated on-line biocide sensor based on dimedone assay is underway.

关键词： DNA Staining Automated Monitoring Autonomous Microbe Sensor Microbial Sensor Prototype Injection Seawater

In vivo subsurf.ce morphological and f.nctional cellular and subcellular imaging of.the gastrointestinal tract with conf.cal mini-microscopy

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World Journal of.Gastroenterology 2007年第15期13卷 2160-2165页

作者： Martin Goetz Beena Memadathil Stef.n Biesterf.ld Constantin Schneider Sebastian Gregor peter R Galle Mark.s f.Neurath Ralf.k.esslich Medical Clinic Johannes Gutenberg-Universit(a|¨)t MainzGermany Department of.Pathology Johannes Gutenberg-Universit(a|¨)t MainzGermany

AIM： To evaluate a newly developed hand-held conf.cal probe f.r in vivo microscopic imaging of.the complete gastrointestinal tract in rodents. METHODS： A novel rigid conf.cal probe （diameter 7 mm） was designed with optical f.atures similar to the f.exible endomicroscopy system f.r use in humans using a 488 nm single line laser f.r f.uorophore excitation, Light emission was detected at 505 to 750 nm. The f.eld of.view was 475 μm × 475 μm. Optical slice thick.ess was 7 μm with a lateral resolution of.0.7 μm. Subsurf.ce serial images at dif.erent depths （surf.ce to 250 μm） were generated in real time at 1024 × 1024 pixels （0.8 f.ames/s） by placing the probe onto the tissue in gentle, stable contact. Tissue specimens were sampled f.r histopathological correlation.RESULTS： The esophagus, stomach, small and large intestine and meso, liver, pancreas and gall bladder were visualised in vivo at high resolution in n = 48 mice. Real time microscopic imaging with the conf.cal minimicroscopy probe was easy to achieve. The dif.erent staining protocols （f.uorescein, acrif.avine, f.TC-labelled dextran and L. esculentum lectin） each highlighted specif.c aspects of.the tissue, and in vivo imaging correlated excellently with conventional histology. In vivo blood f.ow monitoring added a f.nctional quality to morphologic imaging.CONCLUSION： Conf.cal microscopy is f.asible in vivo allowing the visualisation of.the complete GI tract at high resolution even of.subsurf.ce tissue structures. The new conf.cal probe design evaluated in this study is compatible with laparoscopy and signif.cantly expands the f.eld of.possible applications to intra-abdominal organs. It allows immediate testing of.new in vivo staining and application options and theref.re permits rapid transf.r f.om animal studies to clinical use in patients.

关键词： Conf.cal microscopy in vivo imaging Endomicroscopy f.uorescence

Nutritional and Technological Characteristics of.New Cowpea (<i>Vigna unguiculata</i>) Lines and Varieties Grown in Eastern k.nya

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f.od and Nutrition Sciences 2020年第5期11卷 416-430页

作者： peter k. Biama Abdul k. f.raj Christopher M. Mutungi Isaac N. Osuga Rose W. k.ruma Dairy and f.od Science and Technology Department Egerton University Nakuru Kenya International Institute of.Tropical Agriculture (IITA) Dar es Salaam Tanzania Department Animal Science School of Natural Resource and Animal Sciences Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya k.nya Agricultural and Livestock.Research Organization (k.LRO) k.tumani Kenya

Protein sources in the diet of.people living in semi-arid land of.k.nya are lack.ng and if.available it is costly to them. In terms of.saf. f.od and a healthy f.od supply, cowpeas (Vigna unguiculata.) are a signif.cant source of.protein, carbohydrates, and minerals especially f.r poor populations in the k.nya, it is said to be poor man’s meat. The aim of.this study was to determine nutritional composition of.newly bred ten cowpea lines and f.ve varieties commonly grown in Eastern k.nya of.k.tui, Machak.s and Mak.eni counties to understand their potential utilization in curbing rising f.od and nutrition insecurity in arid and semi-arid lands ASALs and in any other f.od applications in k.nya. The experiment was arranged in Completely Randomized Design (CRD) whereby proximate composition and minerals were determined using standard AOAC and AACC methods and technological characteristics check.d using modif.ed methods used by other researchers. Collected data were subjected to Analysis of.Variance (ANOVA) using SAS (2006) version 9.1, mean separation was done using Tuk.y’s Honestly Signif.cant Dif.erence (HSD) method at 5% level of.signif.cance. Cowpeas composition ranged f.om 12.28% - 13.35% f.r moisture content, 49.37% - 55.74% f.r total carbohydrates, 2.99% - 3.34% f.r crude ash, 0.13% - 0.81% f.r crude lipids, 23.37% - 29.70% f.r crude protein and 1.40% - 4.34% f.r crude f.bers. Cowpea samples recorded highest percentage of.essential amino acids (60.71%) and non-essential amino acids (39.29%). Minerals ranged f.om 1.97 - 2.69 mg/100g f.r calcium, 3.23 - 3.90 mg/100g f.r magnesium, 205.53 - 223.30 mg/100g f.r sodium, 0.80 - 1.23 mg/100g f.r zinc, 1071.15 - 1152.62 mg/100g f.r potassium and 0.62 - 1.06 mg/100g f.r phosphorus. f.r technological properties, lines absorbed water equivalent to their weights and they were comparable to varieties grown in the region. f.om the results it showed that cowpea line IT97k.1042-3, TEXAN PINk.YE, TX123, IT85f.867-5, IT82D-889-1 and

关键词： Cowpea Lines Varieties Eastern k.nya Nutritional Technological Characteristics

Peeling of. the surf.ce: Pt-decoration of.WSe 2 nanof.ak.s results in exceptional photoelectrochemical HER activity

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SusMat 2022年第6期2卷 749-760页

作者： peter S.Toth Gabor Szabo Gabor Bencsik.Gergely f.Samu k.ishnan Rajeshwar Csaba Janak. Department of.Physical Chemistry and Materials Science Interdisciplinary Excellence CenterUniversity of SzegedSzegedHungary Department of.Chemistry and Biochemistry The University of Texas at ArlingtonArlingtonTexasUSA

Photoelectrochemical(PEC)hydrogen evolution reaction(HER)was studied on exf.liated,pristine and Pt-decorated tungsten diselenide(p-WSe_(2))nanof.ak. samples,using a previously developed microdroplet PEC microscopy *** WSe 2 nanof.ak.s had well-def.ned thick.esses as measured by atomic f.rce microscopy,and the Pt nanoparticles(NPs)were deposited by a variable num-ber of.atomic layer deposition(ALD)*** exceptionally high photocurrent density of.49.6 mA cm^(−2)(under 220 mW cm^(−2) irradiation)and internal-photon-to-electron-conversion ef.iciency(∼90%at 550 nm)were demonstrated on these Pt-decorated WSe_(2)(WSe_(2)-Pt)*** Pt NP loading and thick.ess of.WSe_(2) nanof.ak.s(in the 24–235 nm range)were used to f.ne-tune their PEC activity f.r *** f.und similar charge transf.r and surf.ce recombination k.netics of.pristine and WSe_(2)-Pt specimens(as assessed by intensity-modulated photocurrent spectroscopy),which indicated signif.cant dif.erences in their bulk.properties.X-ray and ultraviolet photoelectron spectroscopies were perf.rmed to identif. def.ct states and quantif. the density of.states around the valence band of.WSe_(2).The elevated temperature of.the ALD process and the evolving Pt NP phase conspired to passivate the sub-surf.ce(i.e.,bulk.def.cts in the WSe_(2) nanof.ak.s,resulting in their vastly improved PEC perf.rmance.

关键词： atomic layer deposition def.ct migration density of.states hydrogen evolution layered semiconductor photoelectrochemical k.netics